Knurled piston ring arbor



July 25, 1933. T. E. McFALL KNURLED PISTON RING ARBOR 2 Sheets-Sheet 1 Filed April 21, 1930 no ell T o1: Thutlou E H YQU -f v July 25, 1933. T. E. M FALL KNURLED PISTON RING ARBOR Filed April 21, 1950 2 Sheets-Sheet 2 Patented July 2 5, 1933 reunion/ E. MCFALL, or SPARTA/MICHIGAN,

' KNUBLED Heron RING AR OR" Application filed April 21,

This invention relates to an-arbor for holding piston ring castings which are against movement in proper relation to each other and to cutting or splitting'saws therefor, for 1:. the purpose of evenly dividing doublewidth piston ring castings midway between their I 'oppositeflat sides. I have heretofore obtained Patent No. 1,749,147, issued March 4th, 1930, for a process of piston ring cast- I ing production the essentials of which is the production of castings of double width, plus the necessary allowance for shrinkage and machining and a division ofeach double Width ring casting into twoequal parts,

3;, producing .ingle ring castings of uniform character, with a complete absence of hard spotsdue to chilling, pressuresand the like during the periodthat the molten iron is hardening. I 1 It is a primary object andv purpose of the present invention to provide a mechanism for the effective holding'of a plurality of the 1 ring castings side by side upon an arbor, and securing them against movement whereby each of the ring castings may be acted upon by a saw or equivalent cutter to thereby split each double width ring casting into two substantially like parts of thesamewidth or Whose variationsxa're well within'the limits so of tolerance permitted. The invention. is fully set forth in the following description, taken in'connection with the accompanying drawings, inwhich, i V, Fig. 1 is an elevation illustrating the arbor of my invention holding a plurality ofthe ring castings and being acted upon by the saws.

1F ig. 2 is an end elevation p of the construction shown in Fig. 1. g I

4K1 Fig. 3 is a somewhat enlarged'longitudinal vertical section through the arbor before its expansion to engage with the inner curved sides of the ring castings.

Fig. 4 is a View similar to Fig. 3 showing the arbor after its expansionto snugly engage against the inner sides of the ring casting.

Fig. 5 is a fragmentary enlarged section and elevation illustrating the manner in which the saws'split the ring castings each i 50 into two parts.

two likeparts, Like reference characters refer "to; like Y parts in thedifi'erent figures offthedrawings' screws 5thread through the plate 3'parallel it spring 9 or equivalent device seats inall of the which will hereafter described;

1930. Serial No. 445,947. g

Figs. 6 and? are opposite endielevationsf of the arbor. .j

, Fig. 8 is-afragmentary side elevation-of the arbor, the parts atone end. of the arbor being removed, and Y 1 j ,Fig. 9 is a perspective :view of a double width ring casting with a dotted line-indication of how the same-isrdivided or split into 'In the construction ofthe arbor, a shaft 1 of suitable length is providedwhich,uata

plurality of spaced apart points,is formed with conical sections 2. Adjacent one end of the shaft a circular plate?) is mounted, it being providedwitha hub throughwhich and the shaft a securing pinA may bel passed to fix the plate to the shaft. Anumber of to the axisof the shaft 1 andare adJustable to different positions, having the usuallock-' :ing nuts'for. securing thescrewsin any position to.Wl1ich adjusted. I? Around and lengthwise of the shaft'l series of arbor membersfi are located. 'Each 'islformed" at it's innerside with inwardly extending ribs .7 the inner edges of which; are

inclined tocorrespond with theinclinations i x of the conical sections 2 againstWhich they bear. Preferably, four ofthe arbor members 6 willbe used though the invention is in no sense limited: to'such particular number of arbor members; Itisevident that on longi tudinal movement of the arbor members toward the plate3the same are moved radially outward and on longitudinal movement in the opposite direction they will move'inward through the inner edgeslof the ribs 7 ridingv on thecconical surfaces of the sections 2 of the shaft. Atthe ends 8 ofthe arbor. members nearest the plate 3, each is provided with a grooveat its outer side'and a'coiled tension grooves of all of said arbor members. The outside diameter of the groovede'n'd portions 8 is greater than the diameter of the outer surfaces of the arbors, in this manner forming outwardly extendingflanges the purpose of neaith :each ring casting,

The opposite ends of the arbor members 6 are reduced considerably 1n diameter and each is similarly grooved making grooved ends 10 in which a second coiled tension,

spring 11 is located. The coiled tension spring members 9 and 11 have the effect of automatically moving the arbor members to their collapsed position, causing the ribs 7 to ride inwardly on the conical sections 2 of the shaft when said arbor members are free for such movement.

The outercurved surface of each of the arbor members 6 is provided with a consecutive series of spaced apart narrow grooves 12, and the grooves in all of the arbor members are in alinement around the arbor. The.

projecting portions or tongues 13 between the grooves 1 2 are rou hened at their outer surfaces. They may be ridged or file'cut di I a onall as shown in Fi 8 or knurled or any other equivalent roughened surface 'which will engage the inner sides of the piston ring casting 14 located thereover may be used or the outer sides of the arborsbetween the grooves 1 2 may carry rubber strips which serve as friction retaining members for the ringcastings upon outward expansion of the arbor members 6 to bring the same against the inner sides of the ring castings. The ring castingsl t are readily placed over the smallergrooved ends 10 of the arbor member 6 and the first one placed thereover comes "against the flanges provided by the grooved #ends 8 as previously described.

l iyafter they have been "molded and cast,

so'that the ring casting has a certaln width "of face within tolerance limits of one-half thousandth 'nch whereby when a number of them are iplaced over the arbor members, the grooves 12 in said members are located mid- Way between the parallel flat sidesof the ring castings, there being a groove underas best shown in and 4.

The outer-end of'the shaft-1 is exteriorly threaded as indicated at 1a and is provided with a 'keyway slot. A second circular plate 15 has a'cent-ralhub 16 which allows the same to he-slid over the end lavofthe shaft, and the'hub has a key to follow the key-way slot 'to hold the :plate from rotation, but permitting movement lengthwise of the shaft. A

17 ,provided with an annular flange or lip 18 at its inner side, is connected to the plate 1'5'at the inner side thereof by means a number 'of studs or headed screws 19 which pass freely through openings in the plate 15 and-are threaded into the ring. Be-

tween the inner side. of the plate 15 and the :17 a plurality of coiled springs 20 are located and held, the tendency of which is to v move the ring 17 from the plate 15 as far as 5; permitted, or until the heads ofthe studs 19 of the screws 5.

Inpracti-ce the double-width ring castings A nut 21 threads onto the outer end of the shaft 1a. v V

In placing a plurality .of the ring castings 14:. over the arbor, the nut 21 and the plate 15 with the attached ring 17 are removed, whereupon the springs 9 and 11 .cause the arbor members to move inwardly to the position shown in Fig. 3 and a plurality of ring castings are readily placed over the arbor. The ring 17'and plate 15 are thenplaced over the end 1a of the arbor and the nut 21 threaded thereon against said plate 15. The plate is brought against theends 10 of the arbor members moving them longitudinally and cansing the inclined inner edges of the ribs 7 to ride outwardly on the inclined sections 2 of. the shaft 1 until the opposite ends 8 of said arbor members abut against the ends This forces the arbor members outward so that the grooved, knurled or roughened outer surfaces 13 are pressed very firmly and snugly against the inner curved surfaces of the ringcastings. In practice the ring castings are of the well known out-of-round form, made by the insertion of a gap piece-or segment in a circular pattern split atone side to receive said segment. The surfaces of the arbor members 6 are arcs of cylinders whereby, when thearbor is expanded in the manner described, the ring castings are distorted from their out-of-round form to" circular form, it being evident that the pressure of the arbor members 6 against the inner sides of the rings is necessarily heavy to produce such distortions. lVith the knurled or roughened outer surfaces of the arbor members 6 there is a very firm engagement of the ring castings with the arbor members,;or twisting or binding when the-cutting saws act upon the rings. The ring castings of course are held snugly against each other by the pressure of flange 18 ofthe spring actuated ring 17 before the arbor membersare moved far enough outward to engage againstthe inner sides of the castings. Said pressure is a yielding pressure and in no way great enough to interfere wtih the sliding of the ring castin.gs, at their contacting sidesyloy each other when'the expanding arbor members 16 engage thereagainst; it being evident that the ring castings in the first instance are placed loosely over the collapsed arbor membersand do not assume the smooth fornrthat-they have, in dicated, attheir outer sides in Fig. 4, after the expansion of the arbor has been completed.

The extent of the outward or expanding movement of the arbor members 6 is gauged by the position of the screws 5. And it is apparent that the force with which the arbor,

.when fully expanded, engages against the inner sides of the ring castings may be readilycontrolled and changed by an a'd uStment of said screws.

An arbor loaded witlrring castings 14 and fully expanded hassuch' ring castings located.

One end of the shaft l is adapted to detach-' ably connect with the head stock 22 of a lathe or similar machine, and the other end with the tail stock spindle 23. A saw arbor shaft 24 has a plurality of saws 25 mounted thereon spaced apart from each other and held in parallel relationby spacing collars 26. This plurality or gang of saws is mounted so as to be fed to the ring castings at a side of the casting holding arbor preferably, and the saws rotating-rapidly, and thearbor shaft also being turned, the saws readily split each ring casting 14 midway between its parallel or flat sides as 'indicated'in dotted lines at 27, in

Fig. 9,idividing, each ring casting-into two equal parts each of which may be readily utilized thereafter for making a piston ring.

The grooves 12 are in the planes ofthe saws so thatcsaid saws may be out entirely through the castings. I

It is to he understood that, so far the inventionberein is concerned, cutting tools 'tation on the invention should be made that the arbor must be usedwith a saw or gang of saws.v I Likewise, for a shorterlength of arbor only one of the conicalenlargementsfl will be used with a cooperating rib T on the expanding arbor members.

The construction is one which has been produced after a considerable experiment and trial and after the production of various otherarbors for attaining the same end as shown in prior pending applications fol-patent filed by me. Splitting the piston ring castings midway between their flat sides is readily accomplished in a very rapid and efficient manner. The invention is defined in the appended claims and is within their scope.

I claim:

1. In a construction of the class described,

a shaft, a plurality of arbor members around the shaft in spaced apart relation to each other and located lengthwise of the shaft, inter-engaging means between the shaft and inner sides of said arbor members for moving said members radially outward on longitudial movement thereof in one direction along the shaft, means adjacent one'end of said members for stopping the movement of the arbor members along the shaft, a plate slida- V bly mounted on said shaft at the opposite end 60,

of the arbor members, means for moving said plate along the" shaft to engage, with said opposite end of the arbor members and move them longitudinally, a ring movably mount ed on said plate at the: inner side thereof and springs between the plate and ring tending to to be considered ring casting.

force the ring'away from the plate, whereby when ring castings are placed around the arbor member said rlngyic-ldingly engages against the last of said ring castings placed, on the arbor andserves to yieldlngly press all of the ring castings contacting'sidesl 1 w 2.; In a construction-of the class described,

snugly together at'their a horizontal shaft, a plurality of arbormemhers located around and lengthwise ofthe shaft in spaced relation to each other, each of said arbor members'at one end having, an outwardly extending a flange, interengaging means onjthe shaft and arbor members for 'moying said. members radially outward on longitudinal movement thereof .in one direc- 1 uralong the shaft,stop means'niounted on tl shaft against which one end of saidarbor members eng to limit the longitudinal movement thereof, said arbor members being adapted to have plurality of'doubl ewidth ring eastim loca d thereoverwith the first r ng 'castmgplaced thereon bearing aga nst li-ll fl'lli fi at sa id, end of the arbor members,

:1, pl dablv untedon the s'hafta'dja- (:e a, n e'oppo send of the arbor in 'mhers and movableto engage I therewitl a nut Y' P i 7 threaded onto said end'of the shaft to move the plate into engagement with the ends of the arbor memberma ring around theshaft at theinner side of said plate, headed screws" passmgfreely through said'plate and threaded into said ring, and coiled compression sp'rinps between said plateandring. substantially as and, for the purposes described. A construction containing the elements in combination defined in claim2, said arbor,

members at their outer surfaces having a plu rality of narrow grooves therein in spaced apartrelation to each. other and around the.

arbor members, the surfaces of, said arbor members between said grooves having means to securely engage against the inner sides of ring castings against movement on outward in combination defined in claim 2, said arbor members having a plurality of narrow grooves in spaced apart relation to each other at and around theoutersurfaees of said mem bers, said grooves being located with reference to piston ring castings placed over the arbor members such that each ring casting has a groovelocated thereunder substantially midway between the 5; A construction containing the elements 'in combination defined in claim 2, said arbor members having a pluralltyof spaced apart' narrow grooves in and around the outer surfaces thereof, sa d grooves being located to plston ring castings placed over the arbor members such that each ring casting has a" groove located under it substantiallymidway parallel flat sides of the between the parallel fiat sides of the casting, andthe surfaces of said arbor members between said grooves being roughened to secure- 1y engage with the inner sides of the ring castings when the arbor members are moved outwardly into engagement therewith.

6. In a Construction of the class described, a horizontal shaft, a plurality of arbor mem bers located around the shaft and lengthwise thereof, interengaging means between the shaft and inner sides of said arbor members for moving said members radially outward on longitudinal movement thereof in one directiOn along the shaft, means for moving said arbor members lengthwise of the shaft to expand the sameoutwardly, means to stop the longitudinal movement of said members, and means to yieldingly hold the piston ring castings against each other during and prior to the time of radial outward movement of said arbor members.

7. In a construction of the class described,

a shaft having a plurality of spaced conical thereof and spaced from each other at their edges and provided at their inner sides with cooperating inclined sides to engage against said conical enlargements on the shaft, each of said arbor members at one end having an outwardly extending flange to serve as stop means for the first ofaplurality of piston ring castings placed over the arbor members-# and means for moving the shaft and arbor J members longitudinally with respect toeach other to move said arbor members radially outward and thereby firmly engage the inner surfaces of said'rings, said means also being- 7 arbor members lengthwise of the shaft to eX- pand the same outwardly, means to stop the longitudinal movement of said members, and means to yieldingly hold the piston rmg'cast- :ings against each other during the time o f Q radial outward movement of said arbor members.

THURLOW E. MoFALL. 

